mail

Documentation

Overview

Package mail implements parsing of mail messages.

For the most part, this package follows the syntax as specified by RFC 5322 and extended by RFC 6532. Notable divergences:

• Obsolete address formats are not parsed, including addresses with embedded route information.
• The full range of spacing (the CFWS syntax element) is not supported, such as breaking addresses across lines.
• No unicode normalization is performed.
• The special characters ()[]:;@\, are allowed to appear unquoted in names.
• A leading From line is permitted, as in mbox format (RFC 4155).

Index

• Variables
• func ParseDate(date string) (time.Time, error)
• type Address
  • func ParseAddress(address string) (*Address, error)
  • func ParseAddressList(list string) ([]*Address, error)
  • func (a *Address) String() string
• type AddressParser
  • func (p *AddressParser) Parse(address string) (*Address, error)
  • func (p *AddressParser) ParseList(list string) ([]*Address, error)
• type Header
  • func (h Header) AddressList(key string) ([]*Address, error)
  • func (h Header) Date() (time.Time, error)
  • func (h Header) Get(key string) string
• type Message
  • func ReadMessage(r io.Reader) (msg *Message, err error)

Examples

• ParseAddress
• ParseAddressList
• ReadMessage

Variables

var ErrHeaderNotPresent = errors.New("mail: header not in message")

Functions

func ParseDate

func ParseDate(date string) (time.Time, error)

ParseDate parses an RFC 5322 date string.

Types

type Address

type Address struct {
	Name    string // Proper name; may be empty.
	Address string // user@domain
}

Address represents a single mail address. An address such as "Barry Gibbs <bg@example.com>" is represented as Address{Name: "Barry Gibbs", Address: "bg@example.com"}.

func ParseAddress

func ParseAddress(address string) (*Address, error)

ParseAddress parses a single RFC 5322 address, e.g. "Barry Gibbs <bg@example.com>"

Example

package main

import (
	"fmt"
	"log"
	"net/mail"
)

func main() {
	e, err := mail.ParseAddress("Alice <alice@example.com>")
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println(e.Name, e.Address)

}

Output:

Alice alice@example.com

func ParseAddressList

func ParseAddressList(list string) ([]*Address, error)

ParseAddressList parses the given string as a list of addresses.

Example

package main

import (
	"fmt"
	"log"
	"net/mail"
)

func main() {
	const list = "Alice <alice@example.com>, Bob <bob@example.com>, Eve <eve@example.com>"
	emails, err := mail.ParseAddressList(list)
	if err != nil {
		log.Fatal(err)
	}

	for _, v := range emails {
		fmt.Println(v.Name, v.Address)
	}

}

Output:

Alice alice@example.com
Bob bob@example.com
Eve eve@example.com

func (*Address) String

func (a *Address) String() string

String formats the address as a valid RFC 5322 address. If the address's name contains non-ASCII characters the name will be rendered according to RFC 2047.

type AddressParser

type AddressParser struct {
	// WordDecoder optionally specifies a decoder for RFC 2047 encoded-words.
	WordDecoder *mime.WordDecoder
}

An AddressParser is an RFC 5322 address parser.

func (*AddressParser) Parse

func (p *AddressParser) Parse(address string) (*Address, error)

Parse parses a single RFC 5322 address of the form "Gogh Fir <gf@example.com>" or "foo@example.com".

func (*AddressParser) ParseList

func (p *AddressParser) ParseList(list string) ([]*Address, error)

ParseList parses the given string as a list of comma-separated addresses of the form "Gogh Fir <gf@example.com>" or "foo@example.com".

type Header

type Header map[string][]string

A Header represents the key-value pairs in a mail message header.

func (Header) AddressList

func (h Header) AddressList(key string) ([]*Address, error)

AddressList parses the named header field as a list of addresses.

func (Header) Date

func (h Header) Date() (time.Time, error)

Date parses the Date header field.

func (Header) Get

func (h Header) Get(key string) string

Get gets the first value associated with the given key. It is case insensitive; CanonicalMIMEHeaderKey is used to canonicalize the provided key. If there are no values associated with the key, Get returns "". To access multiple values of a key, or to use non-canonical keys, access the map directly.

type Message

type Message struct {
	Header Header
	Body   io.Reader
}

A Message represents a parsed mail message.

func ReadMessage

func ReadMessage(r io.Reader) (msg *Message, err error)

ReadMessage reads a message from r. The headers are parsed, and the body of the message will be available for reading from msg.Body.

Example

package main

import (
	"fmt"
	"io"
	"log"
	"net/mail"
	"strings"
)

func main() {
	msg := `Date: Mon, 23 Jun 2015 11:40:36 -0400
From: Gopher <from@example.com>
To: Another Gopher <to@example.com>
Subject: Gophers at Gophercon

Message body
`

	r := strings.NewReader(msg)
	m, err := mail.ReadMessage(r)
	if err != nil {
		log.Fatal(err)
	}

	header := m.Header
	fmt.Println("Date:", header.Get("Date"))
	fmt.Println("From:", header.Get("From"))
	fmt.Println("To:", header.Get("To"))
	fmt.Println("Subject:", header.Get("Subject"))

	body, err := io.ReadAll(m.Body)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("%s", body)

}

Output:

Date: Mon, 23 Jun 2015 11:40:36 -0400
From: Gopher <from@example.com>
To: Another Gopher <to@example.com>
Subject: Gophers at Gophercon
Message body